Different reasons for social withdrawal include a performance deficit, a social skill deficit, lack of peer support, and avoidance of anxiety or aversive interactions. Each of these reasons for social withdrawal may require a different intervention. This study investigated the utility of brief experimental analysis for identifying the most functional intervention to increase positive peer interactions for three socially withdrawn students. Using a multiple baseline and multi-element single subject design, three treatments were administered to compare differences in peer interactions during recess. Interventions were contingent reward, a social skills training with peer mediation, and a brief cognitive-behavioral strategy. Although students responded differently to the three interventions, the social skills training with peer mediation intervention showed the greatest gains for all students during the brief assessment and when implemented over time.